Chimney damper for open fireplaces



Sept. 4, 1945. A. s. GRETH I CHIMNEY DAMPER FOR OPEN FIRE PLACES Filed March 21, 1944 Patented Sept. 4, 1945 UNITED STATES PATENT OFFICE 2,384,249 CHIMNEY DAMPER FOR OPEN FIREPLACES August S. Greth, Oakland, Calif.

Application March 21, 1944, Serial No. 527,429

9' Claims.

This invention is an improvement over conventional chimney extensions and damper arrangements due to the special design of the apparatus and the fact that it is a self-supporting unit which requires no stay or guy wires or props of any kind for support against wind pressure, and that no bolting or other means of fastening is required; that it is simply placed in position, and-when so placed is fully supported by the main chimney and immovably secured thereby.

In addition, the damper mounted within the extension is adjustable to any desired opening and controlled by a lever which extends out from the front of the fireplace so that it will not become sooted to soil the hands, and will not become too warm for convenient and comfortable handling. The damper is so situated that it is easily removed or replaced through the top of the extension, and is so constructed that when closed it will shed any rain or snow that may collect along one or two corners of the chimney proper to keep the greater portion of the inside of the chimney dry, thereby increasing the initial draft when afire is started several times as great and develop full draft in about one-quarter of the time required with an ordinary chimney extension and damper which permits the entire inside walls of the chimney to get wet.

Other objects and advantages of the invention will become apparent as the following description is read on the drawing accompanying this specification, and inwhich:

Fig. 1 is a side elevation of the invention with the fireplace control lever omitted, and with a portion of the side wall removed to show the construction and arrangement of the damper.

Fig. 2 is a front elevation of the invention, including the control ,leverforthe damper as it would be mounted on the side wall of a fireplace, and with a portion of the front wall removed to show the damper construction.

Fig. 3, is a side elevation of the damper control lever and latching mechanism.

The invention consists of a flue having front, back, and side walls, l0, ll,"'l2 and 13, the crosssectional dimensions of which are made to fit snugly inside a main chimney l4, and the front and back walls It) and II terminate at the upper end in a bonnet l5 which extends beyond the side walls to form hoods and which bonnet is provided with gutters l6 which extend from the ends inwardly and to the lower end of the bonnet and terminate on the outside of the front and back walls. These gutters divert water which drains down the end portions of the bonnet, directly to the front and back walls, and prevent the drainage of any water along an edge of thebonnet to trail inside the chimney directly or through capillary attraction.

Without these gutters which constitute one of the essential features of this invention, water draining over the bonnet between the points: I! and i8 would trail along the curved edge l9 and pas into the chimney at the point 2!], and which is well known to be the case with conventional chimney bonnets of that form, and which is now eliminated by these gutters.

Located at a distance preferably about equal to the width of the flue, from the bottom 2|, is a shield and support 22 which rests on top of the main chimney and therefore functions as a support for the auxiliary chimney or chimney extension. This shield peripherally terminates in an apron 23 to encompass the crown of the chimney. This shield therefore has a second function, that of draining all water away from the sides of the extension and top of the main chimney, directly to the outside where none can drain or creep back into the main chimney.

As will be noted, when the support portion 24 of the extension or flue is snugly fitted inside the main chimney and the apron 23 rests on top, the

extension is rigidly secured to withstand any wind pressure which the main chimney is capable of resisting, and that no bolts, screws, props or guy lines are required or could oiler any advantage.

The side walls terminate at 25 to leave an opening at each end with areas at least equal to onehalf of the cross-sectional area of the inside of the flue.

The damper 26 is located at a point where it can be reached conveniently through either of the openings 2'! in the event that removal or replacement is desired, and consists of a main damper member or plate 28 which fits close to the walls of the flue and terminates at one end in a curl 29 to receive a removable pin 30. which has bearings in the side walls l2 and I3, though if desired, the damper can instead be hinged through the front and back walls I0 and II.

A flange 3| is formed up at the other end of the member as shown, and the sides are also flanged up to form a receptacle between the respective flanges and the curl, the side flanges being tapered from the other end to the curl as indicated at 32 and 33, so that when the damper is raised to the dotted position 28, the front flange will prevent the main damper portion 28 from swinging past center, while the tapered side flanges allow the top edge of the front flange to contact the wall of the flue.

Secured to the underside of the member 28 is a counterweight 34 which is formed of a piece of flat stock depending at right angles to the bottom of the damper and at right angles to the axis of the pivot 30, with the counterweight edgewise to the flow of gases for minimum obstruction. A shelf 35 supports the front end of the damper, and similar narrow shelves may be provided for the sides, and for the back below the curl to form a complete sea1 should such be desirable, as shown. It will be noted that when this damper is closed, or partly closed, that if rain or snow blows through the openings 21 in the bonnet, it will be collected by the damper and will then drain through the recesses 36 at one or both ends of the curl 29 and thus can only drain down the inside of the chimney along those two corners, with the rest of the inside of the chimney I 4 remaining dry or substantially" so. Then, when a fire is started in the fireplace 31, the gases will travel through a chimney which is dry throughout the greater portion of its inner surface, and the draft will be substantially that of a cold, dry chimney the draft of which increases very rapidly in comparison to that of a wet chimney which must be completely dried and completely heated before maximum draft can be expected, while with a dry chimney, only heating f the inside of the chimney is necessary to develop full draft. Not only is it possible to get a fire started and a good fire developed quicker, but the dispersal of smoke or gas into the roomis maintained at an absolute minimum. The dryness of the chimney is further insured by the gutters I6 which prevent drainage down the four corners of the chimney.

The control mechanism for the damper consists of a lever 38 which is shown pivoted intermediate its length to the back wall l2 at 39. A 'link 40 is pivotally connected at one end to one end of the lever as indicated at 4|, and at the other end to an ear 42 mounted on the underside of the damper as indicated at 43. A flexible member 44 such as a chain or cable is connected to the other end of the lever as indicated at 45.

Mounted on one side wall 46 of a fireplace 31 is a bracket 41 to provide a pivot bearing 48 for the hand-operable lever 49 which has the flexible member 44 attached intermediate its length as indicated at. 50. Mounted on the side Wall 45 is another member which has a plurality of spaced lugs or pins 52, spaced to admit the lever 49 therebetween, and with the inner ends 53 spaced from the wall 46 to clear the lever 49 to permit the lever to be moved to any desired position and then be swung away from the wall and between two of the lugs or pins 52 to secure the damper in any adjusted position.

It will be noted that the handle 54 of lever 49 extends out from the front 55 of the fireplace so that it will not b exposed to the flame or heat within the fireplace and will remain free of soot and will remain substantially cool.

This extension can be made to fit any chimney and is self -supporting because the anchor portion 24 which extends below the skirt 22, projects down into the main chimney and closely fits therein, and its length is suflicient to firmly secure the extension and prevent any side sway because of wind pressure.

The weight of the extension is supported by the skirt 22 which sheds all water which drains down the outside of th flue as also any which normally would be intercepted by the top or crown of the main chimney, and the peripheral apron prevents creepage of any water thereunder. The gutters l6 prevent rain from creeping into the corners of the flue at the openings 21; the damper is adjustable to any desired opening so that the draft can be controlled when there is a fire in the fireplace, and when there is no fire it can be kept closed under severe cold atmospheric conditions and opened to any desired degree under other atmospheric conditions. It therefore has three functions;v that of a draft damper, a ventilation control, and a moisture segregator to keep the chimney as dry as possible inside.

The damper will concentrate the collected moisture over very small areas in the chimney instead of allowing it to disperse throughout the entire inner surface of the chimney, thereby assuring. a. quick build-up of the draft, and requiring only the heating of the walls to develop maximum draft instead of first requiring the drying out of th walls which requires a great deal of heat and time. The damper cannot becomelocked in an open position through overbalancing, and it, including its counterweight, offers a minimum obstruction in the chimney relative tp the advantages gained. Furthermore, if the full area of the main chimney must be maintained, the flue can be made larger above the skirt 22 to compensate for the space taken up by the damper.

I claim:

1. Incombination with a flue, adamper located within said fine and pivoted at one end through the side walls of the fine and having a curl formed upwardly for said pivot at said one end and flanged up at the other end and both sides to form a receptacle for moisture entering the top of the flue and having a single outlet to divert all collected moisture to one corner of the flue to maintain the major portion of the inside of. the fiue dry.

2.; A chimney extension comprising: a flue rectangular in cross-section for mounting on a main chimney; a damper curled up at. one end to coincidently form a bearing and a receptacle wall and fitting in said flue and a removable pivot supported by the walls of said flue and passing through said curl; an upstanding flange along the other end and both sides of said damper to form in connection with said bearing and receptacle wall a receptacle for moisture and a stop against excessive opening of the damper, and a weight suspended from the underside of said damper for urging said damper to close; a lever pivoted intermediately to one side wall of said flue and having an operative connection at one end to said damper, and a suspended flexible connection at the other end; a control lever for pivotal mounting at one end to the side wall of a fireplace and having said flexible connection attached thereto, and having a handle to extend beyond the front of the fireplace to prevent excessive heating of the handle, and means attachable to the side wall of the fireplace for securin said control lever in any of several adjusted positions at will.

3. A rectangular flue; a damper comprising a plate having upturned peripheral walls to form a receptacle for moisture falling within said flue and pivotally supported at one end by the side walls of said flue, and means for adjusting said damper to its open and closed positions, and means for supporting said damper in closed position and simultaneously sealing the clearance between the damper and the walls of the flue.

4. A structure as defined in claim 3; said damper having an opening adjacent one corner to discharge moisture collected by said receptacle down one corner of the flue to maintain the rest of the flue other than the immediate area of said one corner of said flue below said damper substantially dry.

5. A structure as defined in claim 3; a weight rigidly attached to and projecting from the underside of said plate to form an over-balancing weight when the damper is open to urge closing of the damper.

6. A structure as defined in claim 3; said means for adjusting said damper to various open and closed positions comprising; a lever intermediately pivoted to one side wall of said flue; a link having its opposite ends respectively connected to one end of said lever and to said damper, and a flexible connection having one end connected to the other end of said lever, and the other end extending down through said flue, and a weight fixed to and projecting from the underside of said damper to function as an over-balancing weight when the damper is open to urge closure of the damper.

7. A damper for a flue having side walls and a rear wall, said damper comprising a flat plate formed upwardly entirely about its periphery to form a receptacle when the damper is closed for moisture falling within the flue, and. being pivotally supported at its rearward end by said side walls and having a passage adjacent to one corner to drain collected moisture from said receptacle down one corner of the flue to maintain the rest of the inside of the flue below the damper substantially dry; and means manually operable for adjusting said damper to various open and closed positions at will.

8. A structure as defined in claim '7; said flat plate formed upwardly including flanges formed upwardly at the front and both sides and a pintle sleeve formed upwardly along the rearward edge, and the pivotal support comprising a pintle within said sleeve and having its ends supported in said side walls; said means manually operable comprising a lever intermediately pivoted to one side wall and having a link connection at one end to said damper and a flexible connection at the other end and extending throughthe lower end of said flue, and a weight fixed to and projecting from the underside of said plate to urge closure of said damper.

9. A structure as defined in claim 7; said means manually operable comprising; a first lever intermediately pivoted to one side wall and having a link connection at one end to said damper and a flexible connection to the other end and extending through the lower end of said flue, and a weight fixed to and projecting from the underside of said plate to urge closure of said damper; a second lever pivoted to the side wall of a fireplace and having a handle extending outwardly beyond the front of the fireplace to prevent excessive heating of the handle, and having said flexible connection connected thereto, means for releasably securing said second lever selectively in various adjusted positions for adjusting said damper to various degrees of opening.

AUGUST S. GRETH. 

